Peter C. Klatsky

Fibroids and reproductive outcomes: a systematic literature review from conception to delivery

We examined the published relationship between uterine fibroids and reproductive outcomes. Submucosal fibroids had the strongest association with lower ongoing pregnancy rates, odds ratio, 0.5; 95% confidence interval, 0.3-0.8, primarily through decreased implantation. Cumulative pregnancy rates appeared slightly lower in patients with intramural fibroids 36.9% vs 41.1%, which may reflect biases in the literature; however, patients with intramural fibroids also experienced more miscarriages, 20.4% vs 12.9%. Adverse obstetric outcomes are rare and may reflect age or other differences in fibroid populations. Increased risk of malpresentation (odds ratio, 2.9; 2.6-3.2), cesarean (odds ratio, 3.7; 3.5-3.9), and preterm delivery (odds ratio, 1.5; 1.3-1.7) are reported; however, the incidence of labor dystocia was low (7.5%). There was no conclusive evidence that intramural or subserosal fibroids adversely affect fecundity. More prospective, controlled trials are needed to assess the effects of myomectomy. Good maternal and neonatal outcomes are expected in pregnancies with uterine fibroids.

The role of embryonic origin in preeclampsia: a comparison of autologous in vitro fertilization and ovum donor pregnancies.

OBJECTIVE: To compare the risk of gestational hypertension and preeclampsia in pregnancies conceived through standard in vitro fertilization (IVF) using autologous oocytes with pregnancies conceived using donated oocytes. METHODS: We conducted a retrospective, matched cohort study of women undergoing IVF using autologous compared with donor oocytes between 1998 and 2005. Women with live births resulting from oocyte donor pregnancies were matched for age and plurality (singleton or twin) with women undergoing autologous IVF. Primary outcomes were the incidence of preeclampsia or gestational hypertension (with and without proteinuria) in the third trimester. Data on preterm delivery, low birth weight, and embryo cryopreservation were also recorded. RESULTS: Outcome data were available for 158 pregnancies, including 77 ovum-donor recipient pregnancies and 81 pregnancies using autologous oocytes. There were no differences in age, parity, and gestational type between the two cohorts. The incidence of gestational hypertension and preeclampsia was significantly higher in ovum-donor recipients compared with women undergoing autologous IVF (24.7% compared with 7.4%, P<.01, and 16.9% compared with 4.9%, P=.02, respectively). Ovum-donor recipients were more likely than women undergoing autologous IVF to deliver prematurely (34% compared with 19%). This association remained after controlling for multiple gestation (odds ratio 2.6, 95% confidence interval 1.04–6.3). Sixteen pregnancies from cryopreserved embryos were more likely to have hypertensive disorders of pregnancy (odds ratio 5.0, 95% confidence interval 1.2–20.5). CONCLUSION: Pregnancies derived from donor oocytes and cryopreserved–thawed embryos may be at a higher risk for hypertensive disorders of pregnancy. These findings inform future research and help counsel women using assisted reproductive technology. LEVEL OF EVIDENCE: II

Testicular Niche Required for Human Spermatogonial Stem Cell Expansion

Prepubertal boys treated with high‐dose chemotherapy do not have an established means of fertility preservation because no established in vitro technique exists to expand and mature purified spermatogonial stem cells (SSCs) to functional sperm in humans. In this study, we define and characterize the unique testicular cellular niche required for SSC expansion using testicular tissues from men with normal spermatogenesis. Highly purified SSCs and testicular somatic cells were isolated by fluorescence‐activated cell sorting using SSEA‐4 and THY1 as markers of SSCs and somatic cells. Cells were cultured on various established niches to assess their role in SSC expansion in a defined somatic cellular niche. Of all the niches examined, cells in the SSEA‐4 population exclusively bound to adult testicular stromal cells, established colonies, and expanded. Further characterization of these testicular stromal cells revealed distinct mesenchymal markers and the ability to undergo differentiation along the mesenchymal lineage, supporting a testicular multipotent stromal cell origin. In vitro human SSC expansion requires a unique niche provided exclusively by testicular multipotent stromal cells with mesenchymal properties. These findings provide an important foundation for developing methods of inducing SSC growth and maturation in prepubertal testicular tissue, essential to enabling fertility preservation for these boys.

CHARACTERIZATION OF HUMAN SPERMATOGONIAL STEM CELL MARKERS IN FETAL, PEDIATRIC, AND ADULT TESTICULAR TISSUES

Autologous spermatogonial stem cell (SSC) transplantation is a potential therapeutic modality for patients with azoospermia following cancer treatment. For this promise to be realized, definitive membrane markers of prepubertal and adult human SSCs must be characterized in order to permit SSC isolation and subsequent expansion. This study further characterizes the markers of male gonocytes, prespermatogonia, and SSCs in humans. Human fetal, prepubertal, and adult testicular tissues were analyzed by confocal microscopy, fluorescence-activated cell sorting, and qRT-PCR for the expression of unique germ cell membrane markers. During male fetal development, THY1 and KIT (C-Kit) are transient markers of gonocytes but not in prespermatogonia and post-natal SSCs. Although KIT expression is detected in gonocytes, THY1 expression is also detected in the somatic component of the fetal testes in addition to gonocytes. In the third trimester of gestation, THY1 expression shifts exclusively to the somatic cells of the testes where it continues to be detected only in the somatic cells postnatally. In contrast, SSEA4 expression was only detected in the gonocytes, prespermatogonia, SSCs, and Sertoli cells of the fetal and prepubertal testes. After puberty, SSEA4 expression can only be detected in primitive spermatogonia. Thus, although THY1 and KIT are transient markers of gonocytes, SSEA4 is the only common membrane marker of gonocytes, prespermatogonia, and SSCs from fetal through adult human development. This finding is essential for the isolation of prepubertal and adult SSCs, which may someday permit fertility preservation and reversal of azoospermia following cancer treatment.

Optimizing cryopreservation of human spermatogonial stem cells: comparing the effectiveness of testicular tissue and single cell suspension cryopreservation.

OBJECTIVE To determine whether optimal human spermatogonial stem cell (SSC) cryopreservation is best achieved with testicular tissue or single cell suspension cryopreservation. This study compares the effectiveness between these two approaches by using testicular SSEA-4+ cells, a known population containing SSCs. DESIGN In vitro human testicular tissues. SETTING Academic research unit. PATIENT(S) Adult testicular tissues (n=4) collected from subjects with normal spermatogenesis and normal fetal testicular tissues (n=3). INTERVENTION(S) Testicular tissue versus single cell suspension cryopreservation. MAIN OUTCOME MEASURE(S) Cell viability, total cell recovery per milligram of tissue, as well as viable and SSEA-4+ cell recovery. RESULT(S) Single cell suspension cryopreservation yielded higher recovery of SSEA-4+ cells enriched in adult SSCs, whereas fetal SSEA-4+ cell recovery was similar between testicular tissue and single cell suspension cryopreservation. CONCLUSION(S) Adult and fetal human SSEA-4+ populations exhibited differential sensitivity to cryopreservation based on whether they were cryopreserved in situ as testicular tissues or as single cells. Thus, optimal preservation of human SSCs depends on the patients age, type of samples cryopreserved, and end points of therapeutic applications.