Search PubMed⌕ Search

Biomedical subjects

O Hovatta

Publications and source records attributed to O Hovatta.

At least 55 records · Page 3Linked to original sources
PubMed1999

Elective transfer of one embryo results in an acceptable pregnancy rate and eliminates the risk of multiple birth.

To avoid multiple pregnancies without compromising pregnancy rates (PR) is a challenge in assisted reproduction. We have compared pregnancy results among 74 elective one-embryo transfers (group 2) and 94 transfers where only one embryo was available (group 1). All the fresh embryo cycles during 1997 in two clinics in Helsinki were analysed, and cumulative PR among these couples after frozen-thawed embryo transfers up to June 1998 were counted. In group 2, where at least two embryos were available for transfer, and only one was transferred on day 2 or 3, the PR per embryo transfer was 29.7%. In group 1, the PR per embryo transfer was 20.2%. In group 2, the cumulative PR after frozen-thawed embryo transfers was 47.3% per oocyte retrieval. Over the same time, 742 two-embryo transfers were carried out. The PR per embryo transfer was 29.4% in these subjects, but 23.9% of these pregnancies were twins. The implantation rates, as well as the PR, were highest when the embryos were at the four- to five-cell stage on day 2 (35.8 versus 9.7% compared with the two- to three-cell stage, P < 0.001) or at the six- to eight-cell stage on day 3 (45.5%). The PR per embryo transfer was higher when a grade 1 or 2 embryo was transferred compared with a grade three embryo (34. 0 and 26.7% versus 8.8% respectively, P < 0.05). In women 35 years or younger, the PR per elective one-embryo transfer was 32.8%. The corresponding figure in women older than 35 years was 18.8%. On the basis of these results, elective one-embryo transfer can be highly recommended, at least in subjects who are younger than 35 years of age, and who have grade one or grade two embryos available for transfer.

Adult↗
PubMed1999

Serum and follicular fluid leptin during in vitro fertilization: relationship among leptin increase, body fat mass, and reduced ovarian response.

The satiety factor leptin is expressed in several reproductive tissues, but its role in the control of reproductive physiology is not well understood. We studied leptin concentrations in the sera and follicle fluids of 52 women [body fat mass percentage (BFM%) range, 19.6-38.8%] undergoing pituitary down-regulation and ovarian hyperstimulation for in vitro fertilization (IVF) treatment. Fasting serum samples were collected 1) at maximal suppression before the initiation of gonadotropin treatment, 2) at maximal ovarian hyperstimulation, 3) at the time of oocyte retrieval, and 4) 16 days later when all subjects were under exogenous luteal support using 600 mg progesterone daily. Follicular fluid (FF) was obtained at oocyte retrieval from two representative preovulatory follicles in both ovaries. During ovarian hyperstimulation there was a significant 60% increase in serum leptin concentrations from 10.9 +/- 1.1 (SEM) to 15.7 +/- 1.5 ng/mL (P < 0.01) between suppression and maximal hyperstimulation, demonstrating that the ovarian functional state can affect serum leptin concentrations. A serum leptin increase of 22-198% during ovarian hyperstimulation was evident in 43 subjects, whereas in 9, leptin concentrations remained unchanged. A positive correlation between leptin change and BFM% (r = 0.55; P < 0.0005) was observed in the 43 leptin responders. The follicular fluid leptin level was similar to that in serum. In separate linear regression analysis, BFM% contributed to 59-64%, body mass index to 46-56%, and weight to 46-55% (all P < 0.001) of the variability in leptin concentrations at the 4 time points. The 20-fold increase in serum estradiol concentrations during IVF was not significantly correlated with changes in leptin concentrations. On the contrary, the relative serum leptin increase was negatively associated with the ovarian response to hyperstimulation, as revealed by the numbers of follicles (b = -0.28; r2 = 8.1%; P < 0.05) and oocytes retrieved (b = -0.39; r2 = 15.2%; P < 0.01). This relationship was further reflected in a positive correlation between the percent increases in leptin and FSH concentrations (r = 0.39; P < 0.01). The significant relationship of high leptin and reduced ovarian response was also maintained when the cumulative dose of FSH was used as a covariable. Reduced ovarian response was not a function of body mass index, BFM%, basal leptin levels, or insulin concentrations. Fasting serum insulin concentrations remained unchanged in response to IVF, but were positively correlated to serum leptin concentrations at all four time points. Our data suggest that leptin production may be influenced by the ovarian functional state. During IVF a high relative leptin increase is associated with adiposity and a reduced ovarian response. These observations support the possibility that high leptin concentrations might reduce ovarian responsiveness to gonadotropins. Hence, leptin might explain in part why obese individuals require higher amounts of gonadotropins than lean subjects to achieve ovarian hyperstimulation.

Adipose Tissue↗
PubMed1999

Pregnancies in women with Turner's syndrome.

Ovarian failure is a typical feature in Turner's syndrome. Therefore, hormone replacement therapy (HRT) is necessary to achieve the development of normal female sexual characteristics and to prevent cardiovascular complications and osteoporosis. Spontaneous puberty occurs in 5-10% of women with Turner's syndrome, and 2-5% of them become pregnant spontaneously. Sexually active young women with Turner's syndrome need contraception. It can be administered as contraceptive pills, which also serve as HRT. Oocyte donation is now a treatment option for infertility of these women. Excellent results have been obtained with 46% of embryo transfers resulting in pregnancy. The pregnancies carry high risks and have to be followed up carefully. The children born following oocyte donation have no additional risks. Risks can be reduced by transferring only one embryo at a time to the uterus, thus avoiding twin pregnancies. Ovarian tissue from young girls with Turner's syndrome could be cryopreserved for infertility treatment in the future, but the optimal age of ovarian biopsy has to be studied, and methods of replantation and maturation of oocytes in vitro have still to be developed. Fertility counselling has become important in the treatment of girls with Turner's syndrome.

Contraceptives, Oral, Hormonal↗
PubMed1998

Aluminium, lead and cadmium concentrations in seminal plasma and spermatozoa, and semen quality in Finnish men.

Aluminium, cadmium and lead concentrations in the spermatozoa and seminal plasma of 27 employees of two industrial companies, a refinery and a polyolefin factory, and 45 consecutive sperm donor candidates at a sperm bank were studied using atomic absorption measurements. The relationship between metal concentration and parameters of semen analysis was studied. A high concentration of aluminium in spermatozoa was correlated with decreased sperm motility. The concentrations of cadmium and lead were low and did not show any correlation with parameters of semen analysis. Aluminium may be one of the environmental pollutants causing impaired semen quality. The mean sperm concentrations were similar in the factory employees (96 x 10(6)/ml), in the sperm donor candidates of the comparison group (104 x 10(6)/ml) and in 352 donor candidates at the sperm bank of the Family Federation of Finland (107 x 10(6)/ml) between May 1993 and May 1995.

Aluminum↗
PubMed1998

Obstetric and perinatal outcome after oocyte donation: comparison with in-vitro fertilization pregnancies.

The obstetric and perinatal outcome in 51 oocyte donation pregnancies (61 infants) was compared with that of a control group of standard in-vitro fertilization (IVF) patients (97 pregnancies, 126 infants). The oocyte recipients (mean +/- SD age 33.5+/-4.7 years) included 39 women with ovarian failure and 12 women with functioning ovaries. In oocyte recipients, first trimester bleeding (53%) occurred significantly more often than in IVF mothers (31%, P < 0.01). Pregnancy-induced hypertension was observed in 31% of oocyte recipients compared with 14% in IVF mothers (P < 0.05). There was no difference in the duration of pregnancies or in the preterm delivery rate between the two groups. When restricting analysis to singleton pregnancies, 63% of oocyte recipients were hospitalized in the antenatal period compared with 29% in the IVF group (P < 0.001). The Caesarean section rate was 57% in the oocyte donation group and 37% in the IVF group (P < 0.05). Birthweight in singleton pregnancies was similar in both groups. The perinatal mortality rate was 3.3% in the oocyte donation group and 0% in the IVF group. In conclusion, oocyte donation pregnancies are associated with an increased risk compared with IVF pregnancies, but the complications are usually manageable and most oocyte recipients experience a good pregnancy outcome.

Adult↗
PubMed1998

Health and development of children born after oocyte donation compared with that of those born after in-vitro fertilization, and parents' attitudes regarding secrecy.

The health, growth and development of a cohort of children (n = 59) aged 6 months to 4 years and born after oocyte donation (OD) was compared with that from a group of children born after in-vitro fertilization (IVF) (n = 126). The study was performed by questionnaire, and the response rate was 100% in the OD group and 95% in the IVF group. All OD children were healthy. Three IVF children had a neurological disorder. Surgical intervention had been carried out in 8% of the OD and 13% of the IVF children. Height and weight development were normal, and eating and sleeping disorders were uncommon in both groups of children. The IVF mothers more often expressed concern about the child's behaviour than did the OD mothers. Thirty-eight percent of the OD parents and 60% of the IVF parents intended to tell the child about the nature of its conception (P < 0.01). Although oocyte recipients appear to have more complications during their pregnancies than conventional IVF patients, the general health status of OD children aged <5 years is at least as good as that of IVF children. Growth and development in both groups of children is similar to that of the general population.

Body Height↗
PubMed1998

Flow cytometric light scattering analysis, acrosome reaction, reactive oxygen species production and leukocyte contamination of semen preparation in prediction of fertilization rate in vitro.

The effects on fertilization of the morphology of spermatozoa, acrosome reaction, reactive oxygen species (ROS) production, leukocyte contamination and the light scattering in flow cytometry of semen preparation were investigated in 73 couples undergoing their first in-vitro fertilization treatment. All men had normal concentrations of spermatozoa with sufficient motility (> or = 50%) and yield (> or = 6 x 10(6)) in the semen preparation on the day of oocyte retrieval. The light scattering properties of all cells present in the semen preparation, as assessed with flow cytometry, were correlated with fertilization. The proportion of metaphase I oocytes was also correlated with the fertilization rate of all collected oocytes and of metaphase II oocytes. ROS production, leukocyte contamination, spontaneous or calcium ionophore-stimulated acrosome reaction, percentage of normal morphology, and multiple anomalies index had no independent contribution.

Acrosome Reaction↗
PubMed1997

Germ cell apoptosis after treatment of cryptorchidism with human chorionic gonadotropin is associated with impaired reproductive function in the adult.

Cryptorchidism results in impaired fertility. Reduced numbers of testicular germ cells can be shown histologically during the first years of life. The process causing germ cell loss in cryptorchid prepubertal boys is unknown, but it could be the result of a form of programmed cell death known as apoptosis. 25 adult men with a history of surgically treated cryptorchidism were studied, 15 of whom had received an unsuccessful human chorionic gonadotropin (hCG) therapy before orchidopexy. Apoptotic DNA fragmentation was assayed in testis biopsies taken during orchidopexy by end-labeling, both in extracted DNA and histochemically in situ. Only a few scattered apoptotic spermatogonias were seen by end-labeling of biopsies from patients not treated with hCG, whereas more extensive labeling of spermatogonia was seen after hCG treatment. As estimated by gel electrophoresis, the amount of low molecular weight DNA was 4.3-fold higher in the hCG-treated group when compared with the level in scrotal testis of non-hCG-treated patients (P < 0.001). About 20 yr after the biopsy, the low molecular weight DNA fragmentation correlated negatively with the testis volume (r = -0.84; P < 0.001) and positively with serum FSH levels (r = 0.73; P < 0.001). Findings in the semen analysis were similar between the groups. Apoptotic loss of spermatogonia after hCG treatment of cryptorchidism warrants reevaluation of the safety of this treatment.

Adult↗
PubMed1997

Levonorgestrel-releasing intrauterine device can be used in oocyte donors during ovarian stimulation.

Seven oocyte donors with a levonorgestrel-releasing intrauterine device (LNG-IUD) in situ (group A) underwent ovarian stimulation with human menopausal gonadotrophin (HMG) after goserelin down-regulation, in eight treatment cycles. The donors in a control group (group B, n = 16) were comparable in age, body mass index and parity characteristics. There were no statistically significant differences in response to ovarian hyperstimulation between the two groups. The number of oocytes recovered was 12.4 +/- 5.1 (SD) following stimulation with 27.9 +/- 9.3 ampoules of HMG over 11.2 +/- 1.3 days in group A. Following stimulation with 26.2 +/- 6.3 ampoules of HMG over 11.0 +/- 1.0 days, the number of oocytes collected was 13.9 +/- 10.4 in group B. The fertilization rate (2PN/cell) of cells in group A was 63% (62/99) and in group B, 53% (117/220, not significant). The cleavage rate of cells in group A (60%, 59/99) was significantly higher than in group B (47%, 104/220) (P <0.05). On average, two embryos were transferred per cycle. In group A, the pregnancy rate per transfer was 40% (4/10) and in group B, 29% (6/21; not significant). In conclusion, LNG-IUD can be used as a contraceptive method during ovarian stimulation of volunteer oocyte donors.

Adult↗
PubMed1997

Follicular density in ovarian biopsy of infertile women: a novel method to assess ovarian reserve.

The ageing ovary appears to be characterized by depletion of primordial follicles. The relationship between infertility and the number of follicles in the ovarian cortex is not known. Moreover, there are no accurate markers or clinical methods to predict the decline in ovarian reserve. This study investigates the correlation between early follicular follicle stimulating hormone, ovarian size and follicular density in 60 infertile women aged 19-45 years (mean = 34.4 +/- 5.5). An ovarian biopsy was taken from each patient while performing diagnostic laparoscopy (n = 28) or laparotomy for tubal surgery or myomectomy (n = 32). The median number of follicles was similar in tubal and unexplained infertility patients (9.5 versus 5.5). Increasing age showed a significant negative correlation with follicular density and ovarian volume (r = -0.46, P = 0.0003;. r = -0.43, P = 0.0016, respectively). In women > or = 35 years of age the ovarian volume showed a strong correlation with follicular density (r = 0.71, P < 0.0001). Our results indicate that infertile women in their late thirties and over have a decreased ovarian reserve which could possibly be predicted by ovarian volume measurement. Ovarian biopsy may have a place as part of infertility evaluation in older women.

Adult↗
PubMed1997

Extracellular matrix improves survival of both stored and fresh human primordial and primary ovarian follicles in long-term culture.

Ovarian cortical tissue was obtained during gynaecological operations by biopsy or after oophorectomy from 20 women aged 25-42 years. It was placed in organ culture, either fresh or following thawing after cryopreservation, for 1-4 months. The tissue was cut in slices 0.1-0.3 mm in diameter and transferred to 12 mm inserts in 24-well culture plates. These slices were cultured for 4-21 days in either alpha minimum essential medium (alpha-MEM) or Earle's balanced salt solution with added pyruvate. Both media were supplemented with 10% human serum, insulin, gonadotrophins and antibiotics. Half of the inserts were precoated with extracellular matrix (Matrigel). Histological samples revealed that there were viable, non-atretic, primordial, primary and secondary follicles in all the cultures. Mitoses were seen in the granulosa cells of the secondary follicles. Although the proportion of atretic follicles increased during culture, non-atretic follicles were still present after 21 days. After 4-11 days the proportion of viable follicles was significantly higher when cultured in Earle's solution supplemented with pyruvate, than when cultured in MEM (77 versus 38%, P < 0.001). In cultures with extracellular matrix the proportion of viable follicles was significantly higher after 10-15 days than it was without matrix (85 versus 19%, P < 0.001). Culture after thawing frozen ovarian tissue did not affect the density or the proportion of the viable follicles. Two-thirds of follicles in cryopreserved tissue were viable after 10-15 days in culture. The results indicate that it is possible to culture human primary and primordial follicles in vitro, and follicles in cryopreserved tissue are viable.

Adult↗
PubMed1997

Sexual development in patients treated for cryptorchidism.

An analysis of sexual development was carried out in adult patients treated in childhood for cryptorchidism. Forty-seven healthy men served as a control group. The cryptorchid patients had been treated between the ages of 10 months to 13 years and their ages ranged from 16 to 30 years at follow-up. The onset of puberty, and sexual development, were within normal limits in all patients, although spermarche occurred somewhat later in the patients than in the controls. In addition, the patients were on average slightly less sexually active than the controls. Neither age at the time of treatment nor the method of treatment correlated with current sexual activity. The patients with larger testes were, however, sexually more active. Both treatment age and the method of treatment, whether hormonal or surgical, should be selected on the basis of fertility prognosis.

Adolescent↗
PubMed1996

Ultrasonography and colour Doppler flow in the testes of adult patients after treatment of cryptorchidism.

OBJECTIVE: To analyse the prevalence of post-operative structural, parenchymal and vascular testicular abnormalities and the incidence of epididymal abnormalities in adult men treated for undescended testes in childhood. PATIENTS AND METHODS: The testes and epididymi of 76 adult men treated for cryptorchidism in childhood were evaluated 16 to 27 years after treatment, using colour Doppler ultrasonography. RESULTS: The 61 spontaneously descended testes were significantly (P < 0.01) larger (mean [SD], 22 [8] mL) than the 90 undescended testes (13 [6] mL). The echo pattern in all the spontaneously descended testes was normal, whereas in 15 cases (17%) the testicular tissue was abnormal after cryptorchidism. In 12 of these 15 cases, the echo pattern was very irregular, and two other cases had microlithiasis of the testicular parenchyma, one of them bilaterally. No normal testicular artery was detected in two cases (3%) of normally descended testes, against 18 (20%) amongst those with undescended testes. Epididymal abnormalities were found in two (3%) of the group of normally descended testes against 32 (36%) in the undescended group. CONCLUSIONS: Infertility in patients with cryptorchidism may be a result not only of primary parenchymal degenerative changes of the testis directly due to the condition, but also of operative vascular trauma and epididymal anomalies. Operative trauma may be more common than has generally been believed. Ultrasonography is a suitable method to evaluate post-operatively the prevalence of the testicular abnormalities analysed in the present study.

Adolescent↗
PubMed1996

Vas deferens aspiration and intracytoplasmic injection of frozen-thawed spermatozoa in a case of anejaculation in a diabetic man.

By using aspiration from the vas deferens, apparently good quality spermatozoa can be obtained for in-vitro fertilization (IVF) in cases of non-treatable anejaculation. Being squeezed from the epididymis during aspiration, the spermatozoa may be immature and their fertilizing capacity lower than that of ejaculated spermatozoa. Our case report describes a couple who achieved pregnancy when intracytoplasmic sperm injection (ICSI) was carried out with frozen-thawed spermatozoa aspirated from the vas deferens of a man whose anejaculation was associated with diabetes mellitus. In the aspiration, 50 x 10(6) spermatozoa were obtained. One half of them was frozen, and the other half was used fresh for conventional IVF, resulting in total fertilization failure of all the oocytes. The second treatment was ICSI, in which eight out of 11 oocytes injected with frozen-thawed spermatozoa showed normal fertilization. The second frozen embryo transfer resulted in a normal pregnancy.

Adult↗
PubMed1996

Pregnancy resulting from intracytoplasmic injection of spermatozoa from a frozen-thawed testicular biopsy specimen.

A testicular biopsy specimen was taken in connection with scrotal exploration of a healthy 35 year old man who had azoospermia. Bilateral severe scarring of unknown aetiology was found in the exploration, and no epididymal spermatozoa could be obtained. Spermatozoa from the fresh biopsy specimen were used for intracytoplasmic sperm injection (ICSI) on the same day. Two-embryo transfer resulted in biochemical pregnancy. The rest of the biopsy specimen was frozen as small pieces of tissue using glycerol as a cryoprotectant. ICSI was then performed with spermatozoa prepared from the frozen-thawed tissue. One embryo was obtained and transferred. The transfer resulted in pregnancy, and a living fetus was seen in ultrasound scans at the seventh and 16th weeks of pregnancy. It is possible to avoid repeated testicular biopsies by using cryopreservation of testicular tissue.

Adult↗