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PubMed2006

Reproductive factors and breast cancer risk among older women.

Reproductive factors have been shown to affect pre- and postmenopausal breast cancer risk differently, but whether there are additional age-specific differences among menopausal women as they age has not been clarified. We analyzed data from a large population-based case-control study that included 1,508 breast cancer cases and 1,556 controls, aged 20-98 years, who completed an in-home interviewer-administered questionnaire. The following subgroups were created to examine if the associations between reproductive factors and breast cancer risk varied by age- and menopausal-status: premenopausal (n=968), postmenopausal <65 years (n=1,045), postmenopausal >or=65 years (n=958). Among postmenopausal women >or=65 years, ever having breastfed decreased risk (odds ratio (OR)=0.67, 95% confidence interval (CI)=0.48, 0.92), and a strong dose-response relationship was observed for longer durations of breastfeeding (P trend=0.02), with the most pronounced protective effect observed for >or=14 months of breastfeeding (OR=0.40, 95% CI=0.21,0.76). Late age at first birth (AFB) and older age at last birth (ALB) were associated with non-statistically significant increases in breast cancer risk in this older group, while late age at menarche and surgical menopause decreased risk. ORs for multiparity were close to the null. Among premenopausal women and postmenopausal women <65 years, multiparity significantly decreased risk, and older AFB nonsignificantly increased risk. Our findings suggest that the well-known protective effect of multiparity attenuates with older age. Moreover, breastfeeding, one of the few potentially modifiable risk factors for breast cancer, was an important factor in decreasing risk among older parous postmenopausal women.

Adult↗
PubMed2005

Association of acculturation with cesarean section among Latinas.

OBJECTIVES: Examine the association of acculturation and cesarean section after adjusting for clinical and non-clinical factors that could influence clinical discretion in performing the surgery. METHODS: A sample of 2102 low-risk, low-income primarily Mexican Latinas in San Diego County was divided into two groups: primiparas and multiparas. For each parity group, logistic regression was used to assess the association of acculturation and cesarean section. RESULTS: Among multiparous Latinas, the risk of cesarean section for highly acculturated women exceeded the risk for the less-acculturated women, but the result was reverse for primiparous women. The adjusted relative odds of cesarean section were twice as high [OR 2.1, 95%CI 1.1-4.1] for multiparous US-born Latinas relative to multiparous Spanish-speaking women born in Mexico. While for primiparous women this same comparison showed US-born Latinas to be approximately half as likely to have a cesarean delivery [OR 0.4, 95%CI 0.2-0.7]. CONCLUSIONS: In order to reduce the chances of unnecessary cesarean sections among Latinas, the role of acculturation in women who have and have not already given birth needs to be investigated further.

Acculturation↗
PubMed1975

Childbirth education, maternal attitudes, and delivery.

The purpose of this study was to evaluate the effects of a childbirth education program (patterned after the Lamaze procedure) on maternal attitudes and the delivery process. Dependent variables included axniety as measured by the anxiety scale of the IPAT, scores on the Maternal Attitudes to Pregnancy Inventory (MAPI), the duration of labor, and the amounts of premedication and anesthesia administered during delivery. Three groups of pregnant women were used as subjects: 70 primiparous and 48 multiparous women taking a 6 week childbirth education course and 41 multiparous women delivery at the same hospitals but not taking the course. In addition the data on labor duration and amount of medication administered to 1,400 multiparous and 1,015 primiparous patients delivery at one of the same hospitals as the other three groups were examined for comparison purposes. No differences were found between groups on the anxiety measure or on duration of labor. Some differences favoring women who had the childbirth education course were found on the MAPI and the medication and anesthesia measures. It was concluded that the childbirth education course had some beneficial effects.

Anesthesia, Obstetrical↗
PubMed1982

Effect of sulpiride on poor puerperal lactation.

Forty-two primiparous and 54 multiparous women with total yields of milk not exceeding 50 ml for the first 3 postpartum days were treated with 100 mg of oral sulpiride or placebo for 4 days from the third postpartum day. In the primiparous mothers, the mean daily yield of milk in the sulpiride group increased significantly (p less than 0.01) over that in the control group after the fourth postpartum day. Mean (+/- SE) total volumes of milk for the third to fifth postpartum days were 661.5 +/- 64.4 and 441.2 +/- 51.2 ml in the sulpiride and the control groups, respectively. However, in the multiparous mothers, no significant difference between the control and the sulpiride group was noted in total yield of milk, since a good increase in the secretion of milk was obtained without medication in these mothers. Determinations of daily serum levels of prolactin in 20 primiparous women revealed significantly higher concentrations in the sulpiride group. The ratio of primiparous mothers with complete breast-feeding 1 month after delivery was higher in the sulpiride group (55%) than in the control group (30%), whereas there was no difference between the control group and the sulpiride group of multiparous women. These data indicate that poor initiation of puerperal lactation in primiparous mothers can be effectively treated with oral sulpiride.

Adult↗
PubMed1990

Evaluation of a risk scoring system as a predictor of preterm birth in an indigent population.

A risk scoring system designed to predict spontaneous preterm birth was implemented in a large, indigent population as part of a multicenter trial of preterm birth prevention. A total of 7478 women with singleton gestations were screened and followed up prospectively at the Birmingham project center. Patients who had an indicated preterm delivery or a fetal anomaly were excluded from the study population. Analysis by assigned risk score and parity showed that, whereas the sensitivity and positive predictive value were better in multiparous women than in nulliparous women, overall the values were low. Logistic regression analyses of the multiparous and nulliparous populations showed independent sets of significant (p less than or equal to 0.05) risk variables. A history of preterm delivery and a low prepregnancy weight were the most predictive risk factors in the multiparous and nulliparous models, respectively. We conclude that the clinical usefulness of a risk scoring system to predict spontaneous preterm birth in an indigent population is limited.

Age Factors↗
PubMed1992

Parity-associated alterations of medial preoptic opiate receptors in female rats.

Preoptic area opiate receptor density was measured by quantitative autoradiography using [3H]naloxone in female rats during their first and second pregnancies and lactations and in a separate group of ovariectomized, nulliparous animals. Opiate receptor density in the medial preoptic area (MPOA) was elevated on day 12 of gestation in both primigravid and multigravid rats when compared with ovariectomized subjects. MPOA receptor density was reduced in primiparous mothers on day 5 of lactation relative to pregnancy. In contrast, receptor density in the MPOA did not decline in multiparous (second lactation) rats relative to pregnancy levels. Opiate receptor density was significantly higher on day 5 of lactation in multiparous than in primiparous mothers. No difference in receptor density was detected in the adjacent lateral preoptic area among the treatment groups. An examination of hormone titers revealed that basal prolactin levels were significantly higher in primigravid than multigravid rats, and that during lactation prolactin titers were negatively correlated with MPOA opiate receptor density in the primiparous mothers. The data demonstrate that multiple pregnancies and lactations result in changes of MPOA opiate receptor density and of circulating hormone levels. The findings are discussed in terms of the concurrent changes in neural opiate sensitivity associated with multiparity.

Analysis of Variance↗
PubMed1992

Outcome and long-term effects of pregnancy in women with hyperprolactinaemia.

Twenty-four women with high circulating prolactin became pregnant on 39 occasions, of which 32 ended in delivery. Sixteen patients showed radiological evidence of pituitary tumour, 6 exhibited a normal CT and 2 had an empty sella. The pregnancies were induced in 4 patients after successful pituitary surgery, in 3 after surgery and medical treatment, and in the rest by bromocriptine (16) long-acting repeatable bromocriptine (1) and methergoline (1). No major complications related to hyperprolactinaemia or its treatment were observed during pregnancy in the patients or offspring. Prolactin after pregnancy was lower than before (basal 95 micrograms/l, after 1st pregnancy 38 micrograms/l P < 0.002, after 2nd pregnancy 24 micrograms/l P < 0.005 compared to basal prolactin); this prolactin reduction tended to be greater in the 9 multiparous patients, but did not attain statistical significance, probably because the number of multiparous patients was too small. A new empty sella developed after delivery in 4 women and persisted in another 2, all of which were medically treated; prolactin fell in all 6 cases normalizing in 3; 4 of these patients had undergone two or more pregnancies. The mean period of follow-up from the last pregnancy was 41.6 months (8-101). These data suggest that pregnancy may hasten a tendency to spontaneous improvement of hyperprolactinaemia, and multiparity may be beneficial in this way.

Adenoma↗
PubMed1995

Epidemiology of endometriosis among parous women.

OBJECTIVE: To report the prevalence of endometriosis and its associated risk factors among multiparous women, and to determine the relationship between the location and depth of this disease and certain medical and behavioral characteristics. METHODS: Over a 6-year period, 3384 multiparous women underwent laparoscopy for tubal sterilization. Endometriosis was detected in 126 patients (3.7%), who were consequently evaluated for severity of the disease. To conduct a case-control study, 504 patients with no evidence of endometriosis were randomly selected from a group of women who underwent sterilization. Information obtained through physical examination and a self-administered questionnaire was studied by multivariate logistic regression analysis. RESULTS: Most endometriosis lesions were minimal. Factors associated with an increased risk for endometriosis included: advanced age (odds ratio [OR] 2.0, 95% confidence interval [CI] 1.1-3.7), Asian race (OR 8.6, 95% CI 1.4-20.1), long cycle length (OR 1.8, 95% CI 1.1-2.7), one live birth (OR 2.2, 95% CI 1.1-4.3), long duration of intrauterine device use (OR 3.0, 95% CI 1.1-8.1), and long duration of uninterrupted menstrual cycles (OR 2.9, 95% CI 1.3-6.4). Present oral contraceptive use was protective for disease (OR 0.5, 95% CI 0.2-0.9). The role of these factors varied among different disease locations (ovary, uterus and tubes, posterior broad ligaments and cul-de-sac), and depth (superficial or deep). CONCLUSIONS: The prevalence of endometriosis is relatively low among multiparous women, and certain menstrual and reproductive characteristics are associated with its development. Furthermore, the relationship between various factors and endometriosis appears to be site and depth specific. Our findings suggest that asymptomatic endometriosis may be clinically important.

Adult↗
PubMed1987

In vitro replication potential of serially passaged mammary parenchyma from mice with different reproductive histories.

Growth properties of multicellular units (organoids) of mouse mammary parenchyma have been analyzed. These intact units grew differently in collagen-matrix cultures than did dispersed cells prepared from them. The latter actively migrated in the collagen matrix and reorganized themselves into multicellular structures before producing three-dimensional protuberances in gel. Terminal unit (end-bud/alveoli)-enriched fractions grew more extensively than did ducts, as predicted from growth patterns in vivo. To assess the growth potential and the relationships between replication history in vivo and replication potential in vitro in mammary parenchyma, intact terminal units from mammary glands of mice of different ages and with different reproductive histories were isolated and their growth characteristics compared. Terminal-unit organoids were cultured in collagen gel matrix and passaged weekly for up to 5 weeks. Morphology, growth rates, and growth fractions were compared among organoids from young virgin, old virgin, monoparous, and multiparous mice. Morphologies observed in various passages of organoids from the groups of mice were similar. Organoids from old virgin and multiparous mice declined in growth rate for four passages and then growth rate increased again during the fifth passage. (However, fifth-passage organoids failed to form tumors if implanted in syngeneic mice in vivo.) Growth of organoids from either old or young virgin mice was less at any given passage than tissue from multiparous mice of similar age. Growth fractions of organoids from old parous mice were the same as those from old virgin mice but reached the same maximum fraction faster. Later passage organoids from the different mouse groups responded morphologically to the hormone combination of estrogen, progesterone, prolactin, and cortisone but not respond to cholera toxin. These results suggest that an animal's hormonal history (altered profoundly by pregnancy and lactation) may be as important as chronological age in determining subsequent growth potentials of mammary epithelium.

Aging↗
PubMed1983

Characterization of summer infertility of sows in large confinement units.

Data were from 3119 farrowings in three large swine confinement units in eastern North Carolina. Litters were weaned during April through October. Interval to first estrus after weaning was greater during June through September than during other months. The two-way interactions among farm unit, parity and month weaned all affected weaning-to-estrus interval. Conception rate at first estrus was lower for primiparous than for multiparous sows and declined from April through July. Conception rate at first estrus was affected by farm by parity interaction. Weaning-to-conception interval was longer for primiparous than multiparous sows and was longer during June through October. Weaning-to-conception interval was affected by interactions of unit with parity and unit with month weaned. Total pigs farrowed at the subsequent farrowing was affected by unit, parity, length of the previous lactation and the unit x parity interaction. Overall, reproductive performance varied among farm units, was lower in primiparous than in multiparous sows and was reduced during June through October.

Journal Article↗
PubMed1992

Epidemiological study on factors influencing fertility indices in Israeli dairy herds.

The objective of this study was to determine feeding factors connected with differences in the fertility of Israeli Kibbutz dairy herds. In an epidemiological case-control survey, data from 30, low-fertility Kibbutz dairy herds having a mean overall conception rate of 35% in multiparous cows were compared with the data from 30, high-fertility Kibbutz dairy herds having a mean overall conception rate of 48% in multiparous cows. Nutritional factors accounted for 67% of the differences between low-fertility and high-fertility herds in the overall conception rate of multiparous cows, while only 4.8% could be related to the body condition during the dry period. Among the factors which occurred more frequently in the low-fertility than in the high-fertility herds were 1) a higher average protein density and lower energy/protein ratio was fed during lactation and 2) a single feeding group was maintained for all lactating cows. 3) There were phytoestrogens in the silage or alfalfa hay, fed during lactation. 4) Faulty dry period was instituted, which was defined as the presence of at least one of the following three practices: a) the daily feed was above 3 kg of high lactation mix; b) more than 15 Mcal of net energy per day was given during the first part of the dry period; c) more than 30% of the cows were obese during the dry period. Three or more risk factors were found in one high-fertility herd and in 20 low-fertility herds. This finding emphasizes the importance of identifying and removing risk factors as a possible means for improving the reproductive performance of herds.

Journal Article↗
PubMed1995

Estrus synchronization efficiency of PGF2alpha injection in Shorthorn-Hereford and crossbred Charolais cattle not having exhibited estrus at 4 or 7 days prior to treatment.

The objective of this study was to compare the estrus synchronization efficiency of PGF2alpha in cattle (n = 470) not having shown estrus for 4 (D4 treatment) or 7 d (D7 treatment) after onset of the breeding season. The physiological status of crossbred Charolais cows was studied, and their reproductive performance was compared to that of Shorthorn-Hereford cows. The percentage of cows in estrus during the 7 d prior to PGF2alpha treatment was superior (P < 0.01) to that observed during the 4 d preceding PGF2alpha. The daily rates of estrus were similar during the 2 periods. For both the Shorthorn-Hereford (87.8 vs 74.7%; P < 0.03) and crossbred Charolais (87.8 vs 66.3%; P < 0.005) females, the estrus synchronization rate during the 5 d post PGF2alpha was higher in treatment D7 than in the D4 treatment. Therefore, for both Shorthorn-Hereford (92.8 vs 81.4%) and crossbred Charolais (93.1 vs 75.0%) the D7 program permitted insemination in 12 d (before and after PGF2alpha) of a higher percentage (P < 0.01) of females than the D4 program did in 9 d. The intervals PGF2alpha to estrus and their variances were similar for both treatments. The conception rate of Shorthorn-Hereford was the same whether they were inseminated after spontaneous (73.4%) or PGF2alpha-induced estrus (D4 treatment: 78.5%; D7 treatment: 72.2%). However, crossbred Charolais cows inseminated after a PGF2alpha-induced estrus in the D4 treatment had a fertility rate (50.9%) slightly inferior (P < 0.07) to that of cows inseminated after spontaneous estrus (70.1%) or after PGF2alpha-induced estrus in the D7 treatment (67.4%). The reproductive performances of multiparous Shorthorn-Hereford and crossbred Charolais were similar in treatment D7; however, in the D4 treatment, the conception rate of Shorthorn-Hereford was higher than that of crossbred Charolais (81.0 vs 42.9%; P < 0.002). Primiparous crossbred Charolais in the D4 treatment had a slightly lower (P < 0.10) synchronization rate (48%) than nulliparous (71%) and multiparous crossbred Charolais (78%). In contrast, the reproductive performances of nulliparous, primiparous and multiparous crossbred Charolais were similar in the D7 treatment. These results indicate that the efficiency of PGF2alpha to synchronize estrus is greater when the estrus detection period increases from 4 to 7 d before PGF2alpha. Only in the D7 treatment was the fertility rate of crossbred Charolais similar to that of Shorthorn-Hereford.

Journal Article↗
PubMed1983

Maternal immunostimulation of a teratocarcinoma-derived cell line, TerCs.

Since murine teratocarcinomas and early embryos are known to share cell surface antigens, we investigated the possibility of maternal immune responses to normal pregnancy using teratocarcinoma-derived cell lines as targets. We found that an adherent cell population from both the spleen and peritoneum of syngeneically mated 129/SvSl pregnant females stimulated the uptake of [125I]iododeoxyuridine ( [125I]IUdR) by a teratocarcinoma-derived cell line, TerCs in vitro. Adherent cells from multiparous females did not stimulate the growth of other tumor cell lines. However, levels of natural anti-tumor activity detected in peritoneal cell populations of 129/SvSl virgin females were greatly reduced during pregnancy. Peritoneal cells from multiparous females with growth-stimulating activity were retained on nylon-wool columns and not eliminated by treatment with anti-theta antiserum and complement. Peritoneal cells from virgin females, treated with anti-theta antiserum and complement to eliminate cytotoxic lymphocytes, gained the ability to stimulate the uptake of [125I]IUdR by TerCs cells. [125I]IUdR uptake by cultured normal mouse blastocysts was significantly enhanced by peritoneal cells from multiparous females, while cells from age-matched virgin females had no effect. These results suggest that changes in immunocyte populations occur during pregnancy in the mouse; these changes could promote the growth of the embryo in utero.

Animals↗
PubMed1984

Allogeneic reactivity of maternal lymphoid cells during the course of gestation. Modifications and sex differences in a local GVH assay.

The immune reactivity of lymphoid cells from pregnant mice was studied during the course of pregnancy in primiparous and multiparous animals either " isopregnant " (male and female of same strain) or " allopregnant " (male and female differing at H-2), using a local GVH assay (CBA lymphoid cells injected into (CBA X A/J)F1 recipients). The findings were as follows: The lymphoid cell number in the para-aortic lymph nodes ( PALN ) was increased at all stages of gestation. The peak occurred in the 2nd week in primiparity and as early as 60 h after fertilization in multiparity. PALN cell alloreactivity was weak at the beginning and higher than normal in the third week of pregnancy. Spleen cell alloreactivity was increased in the second week and decreased in the third week in primiparous compared with multiparous animals. Anti-paternal alloreactivity exhibited by spleen cells of allogestation was decreased (as compared to cells of isogestation ) especially in primiparous mice, particularly in the third week. At this time, the anti-paternal alloreactivity of PALN cells was increased. The influence of the recipient's sex on GVHR intensity was reversed when the cells were obtained from a pregnant donor, becoming stronger in male compared with female hybrids.

Animals↗
PubMed1989

Intrahepatic cholestasis of pregnancy in twin pregnancies.

To clarify whether the increase in estrogen levels occurring during twin pregnancies (TP) is associated with a greater risk of developing intrahepatic cholestasis of pregnancy (ICP), we followed up 62 consecutive patients with TP and compared them with single pregnancies delivered in our hospital during 1 year. The prevalence of ICP was significantly higher in twin than in single pregnancies (20.9% versus 4.7%, respectively; P less than 0.001). Urinary estriol excretion was also significantly higher in twin compared to single pregnancies, although no quantitative differences were detected in TP with or without ICP. In multiparous patients with a proband TP affected by ICP, the disease recurred only in further TP, emphasizing the important role that estrogens seem to play in the pathogenesis of ICP. In contrast, in multiparous patients with a proband single pregnancy affected by ICP, the disease occurred in 70.5% of their other single pregnancies, suggesting the presence of a metabolic predisposition in these cases. However, in both groups of multiparous women a notable number of single pregnancies were not affected by the disease, supporting the postulate that the pathogenesis of ICP is multifactorial and that some as yet unidentified environmental factor needs to be present in order to develop the disease and also to modulate its expressivity.

Alanine Transaminase↗
PubMed1995

Maternal activity budgets: feasibility of exclusive breastfeeding for six months among urban women in Honduras.

Although exclusive breastfeeding for 6 months is likely to be beneficial for infant health, mothers often cite time pressures as a reason to introduce other foods. Using 12-hr in-home observations at 19 and 24 wk postpartum, we compared maternal activity budgets and time spent breastfeeding among low-income, urban mothers not employed outside the home who exclusively breastfed (EBF) or gave other foods in addition to breast milk (BF+SF). Breastfeeding time was similar between groups (averaging approx 75 min/12 hr) except that multiparous EBF mothers at 24 wk spent more time breastfeeding their infants than did BF+SF mothers. However, total time devoted to infant feeding (including preparation and feeding of solids in the BF+SF group) was significantly greater in the BF+SF group than in the EBF group (except among multiparous women at 24 wk). Feeding frequency per 12-hr averaged 6.7-8.9 in the EBF group and 5.4-8.1 BF + 1.8 meals in the BF+SF group. Both EBF and BF+SF mothers had considerable 'free' time; they spent, on average, 2-3 hr during each 12-hr period resting, chatting or watching TV. Primiparous women tended to spend less time at household chores and child care than multiparous women. Of the BF+SF mothers, 60% said that breastfeeding was 'somewhat' or 'very' time-demanding (vs 15% of EBF mothers), 49% said that it interfered with other activities (vs 6% of EBF mothers), and 26% said that they gave other foods to extend the time between breastfeeds. Although many of the BF+SF mothers knew that giving foods may increase infant illness, there were cultural pressures not to exclusively breastfeed. For example, many introduced solids to their infants prior to 6 months because they believed that infants should 'learn' how to eat other foods, to 'acclimate' the stomach and learn to differentiate flavors. We conclude that time constraints are not a barrier to exclusive breastfeeding in this population, although they may be perceived as a barrier.

Activities of Daily Living↗
PubMed1993

Influence of birth and maternal experience on olfactory bulb neurotransmitter release.

The ewe's ability to selectively recognize her lamb depends upon vaginocervical feedback to the brain stimulating an interest in lamb odours. This process is facilitated by previous maternal experience. We have used in vivo microdialysis to measure changes in the release of intrinsic transmitters in the olfactory bulb (glutamate, dopamine and GABA) at parturition to determine if their release profiles differ depending upon the ewe's past maternal olfactory experience. Glutamate and GABA release increased significantly at parturition in multiparous but not primiparous ewes. Dopamine release increased in both groups but mean basal levels of this transmitter were significantly higher in primiparous ewes during the pre-partum period and the first few hours postpartum. The changes in the underlying neural circuitry which determine these differences are established within 6 h of parturition, as revealed by artificial stimulation of the reproductive tract. This procedure renders the system plastic enabling adoption of strange lambs and, contingent, on this, the release of intrinsic transmitters no longer differs between the two groups of ewes. Pharmacological challenges to the olfactory bulb using retrodialysis in nulliparous and multiparous (maternally inexperienced and experienced) ewes produced significant differences between the groups for induction of glutamate and GABA release, but not that of dopamine. K+ challenges produced greater increases in glutamate and GABA release in multiparous than in nulliparous ewes, while dopamine release did not differ with experience. Glutamate receptor blockade produced increases in glutamate ase without changing GABA release.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2006

Operative vaginal delivery and midline episiotomy: a bad combination for the perineum.

OBJECTIVE: The purpose of this study was to determine the impact of operative vaginal delivery (forceps or vacuum) and midline episiotomy on the risk of severe perineal trauma. STUDY DESIGN: In this retrospective cohort study, we assessed the impact of maternal and obstetric factors on the risk of development of severe perineal trauma (third- and fourth-degree perineal lacerations) for all singleton, vertex vaginal live births (n = 33,842) between 1996 and 2003. RESULTS: Among nulliparous women, 12.1% had operative vaginal delivery, 22.4% had midline episiotomy, and 8.1% experienced severe perineal trauma. Among multiparous women, 3.4% had operative vaginal delivery, 4.2% had midline episiotomy, and 1.2% experienced severe perineal trauma. Controlling for maternal age, ethnicity, birth weight and head circumference, evaluation of the interaction of episiotomy and delivery method revealed that forceps (nulliparous women: odds ratio [OR] 8.6, 95% CI 6.5-10.7; multiparous women: OR 26.3, 95% CI 18.1-34.5) and episiotomy (nulliparous women: OR 4.5, 95% CI 3.7-5.4; multiparous women: OR 14.6, 95% CI 10.4-20.5) were consistently associated with the increased risk of anal sphincter trauma. In fact, the magnitude of effect of the statistically significant synergistic interaction was evidenced by more than 3-fold excess of risk of using operative vaginal delivery alone. CONCLUSION: The use of operative vaginal delivery, particularly in combination with midline episiotomy, was associated with a significant increase in the risk of anal sphincter trauma in both primigravid and multigravid women. Given the reported substantial long-term adverse consequences for anal function, this combination of operative modalities should be avoided if possible.

Adult↗