Also, you may have problems delivering your babies. There is a higher likelihood of undergoing a Cesarean section, which is when the babies are delivered through a surgical opening in your belly. During a fertility treatment cycle when fertility drugs are used with timed intercourse or insemination, your doctor will monitor your cycle very carefully.
The use of fertility medications makes it more likely that one or more eggs will be fertilized. However, if it appears that too many eggs are developing, your doctor may cancel your cycle and tell you not to have an insemination or intercourse to eliminate your risk of multiple births.
It is much less likely that you will become pregnant with triplets or more if only one or two embryos are placed in your womb. Before the placement of these embryos embryo transfer , you and your doctor will decide how many embryos to place in your womb. These guidelines can be found at www. If three or more embryos implant inside your uterus, your doctor may suggest that you undergo a procedure called selective reduction.
This argues against diminished negative ovarian feedback as the primary cause of elevated FSH levels in mothers of dizygotic twins. Our observation of no differences in the secretion of FSH in postmenopausal mothers of twins compared with controls would nevertheless suggest a role for the ovary. It should be noted, however, that under postmenopausal conditions, subtle differences in FSH secretion may easily be obscured by the great hourly and interindividual variability in secretion of this hormone.
Furthermore, it is possible that despite equal levels of hormones exerting negative feedback as measured with immunoassays, differences may exist in biological activity.
However, the inhibin assays that were used only measured intact dimeric hormone, which correlates well with biological activity We cannot rule out the possibility that still unknown ovarian hormones that regulate feedback of gonadotropin secretion are involved. Others claim however, that activin is not involved in the gonadal regulation of the menstrual cycle A logical explanation of our observations would be that differences in response to gonadal feedback signals are present.
A difference in FSH moiety that would result in increased serum half-life, thereby accounting for greater circulating concentrations in the mothers of twins, does not seem likely, because in our study the higher FSH levels can be attributed to a clear increase in the number of pulses. In the first place, the increase only concerned additional FSH pulses without a simultaneous LH pulse. Finally, and probably most convincing, is our observation that none of the dynamic parameters of the LH secretion were different in the mothers of the twins.
In particular, this part of FSH secretion is under the control of negative feedback through inhibin This is also supported by the recent observations in sheep of clear FSH pulses in jugular vein blood without significant LHRH elevations in serially sampled blood from pituitary portal blood vessels Altered activity of such factors are probably involved in the increased number of FSH pulses in mothers of twins.
There are several possibilities for the nature of this ese factor s. In the first place, spontaneous pituitary FSH secretion may occur in temporary bursts independent of any releasing factor. However, there are no data available that would support such a secretory mechanism. Alternatively, mothers of dizygotic twins may have genes that are activated that code for a still-putative separate FSH releasing hormone 29 , 30 , or they may carry mutations in the gene coding for LHRH, resulting in synthesis of an LHRH- like peptide preferably inducing secretion of FSH over LH In our view, it seems valid to assume that an hereditary trait of having dizygotic twins is the result of endogenous hyperstimulation by FSH in a significant proportion of mothers.
Within the specifications of the assay that was used in this study, this observation is usually associated with incipient ovarian failure when observed in regularly menstruating women. This is thought to be caused by a diminished ovarian reserve There are indications that being a mother of a dizygotic twin either on an hereditary or nonhereditary basis is a risk for earlier menopause In the present study however, the postmenopausal mothers of hereditary dizygotic twins did not differ with controls in age at menopause.
This might have been the result of undetectable results because of small sample size, but it may also indicate that incipient ovarian failure and hereditary dizygotic twinning are different entities. On the other hand, the natural rise of follicular phase FSH levels, as observed in general after 30 yr of age, may be the underlying cause of the risk of nonhereditary dizygotic twinning 3 with increased maternal age.
Somewhat to our surprise, we could not show a relation between age and FSH. Probably a substantially larger number of subjects are needed to find these differences. Anyway, it should be noted that not all patients with high FSH levels in the early follicular phase should be considered to have premature incipient ovarian failure. In conclusion, the endocrine hypothesis of an elevated FSH in hereditary dizygotic twinning seems valid.
Our results favor pituitary- or LHRH-independent factors from higher regions of the brain leading to more FSH and hereby causing dizygotic twinning. We thank Dr. Thuys for the help in carrying out all the experiments. Google Scholar. Br Med J. Bulmer MG. Oxford : Clarendon Press. Acta Genet Med Gemellol Roma. J Clin Endocrinol Metab. Ballieres Clin Obstet Gynaecol. Brown JB. Baird DT. J Steroid Biochem. Milham S. Fertil Steril. Nylander PP. Br J Obstet Gynaecol. Clin Endocrinol Oxf.
Without fertility treatments, the odds of conceiving triplets spontaneously is around 1 in 1, For quadruplets, the odds are estimated to be around 1 in , With fertility treatments, the chances of a higher-order pregnancy rise substantially. In , for example, the rate for triplet and higher-order multiples was Estimates are that just over three-quarters of triplets and higher-order multiples are the result of fertility treatments.
Your chances of having twins will depend not just on whether you undergo fertility treatment to conceive but also on your family history, race, age, and many other factors.
These factors are also cumulative. In other words, a tall person with a family history of fraternal twins is more likely to conceive twins during fertility treatments than a short person without any family history of twins. The twin and multiple rates also vary from fertility clinic to clinic. Twin rates differ based on how carefully they track ovulation stimulation during fertility drug use and how many embryos they routinely transfer during IVF.
While having twins may sound like the kind of two-for-one deal any couple would love to have after experiencing infertility, it really is best to aim for one healthy baby.
Your doctor can reduce the odds of multiples with careful monitoring and single-embryo transfer during IVF. However, if you do conceive twins or more, know that good prenatal care can reduce your risk of complications. There are also many positive benefits to having twins.
A family history of identical twins will not necessarily increase your chances of having them yourself, although the offspring of male identical twins are more likely to have them. However, you are more likely to have twins if there are fraternal twins in your family. If there are fraternal twins on both your mother's and father's sides of the family, your chances of having fraternal twins yourself are even higher.
Many of the factors that increase your odds of having twins are out of your control, like your family history and height, for example.
But there are other ways to improve your odds if you're hoping for multiples. Factors that increase the chance of twins include: consuming high amounts of dairy foods, being over the age of 30, and conceiving while breastfeeding.
Many fertility drugs including Clomid, Gonal-F, and Follistim also increase the odds of a twin pregnancy. Get diet and wellness tips to help your kids stay healthy and happy. Adashi EY, Gutman R. Delayed childbearing as a growing, previously unrecognized contributor to the national plural birth excess. Obstet Gynecol. Multiple pregnancy and birth: Twins, triplets and high-order multiples.
Trakia J Sci. Gleicher N. Principles of Medical Therapy in Pregnancy. Steinman G. Mechanisms of twinning: VIII. Maternal height, insulin-like growth factor and twinning rate. J Reprod Med. Mechanisms of twinning. Sex preference and lactation. Shur N. The current findings strongly support the hypothesis that the well-documented increased prevalence of twin pregnancy in the fertile advanced age group is because of an increased tendency towards multiple follicular development.
This, in turn, is associated with FSH concentrations induced by the negative feedback mechanism, which overshoot the threshold of ovarian follicle response in this age group. Hum Reprod Update 5 , — Clarendon Press, Oxford.
Fertil Steril 60 , — Int J Epidemiol 10 , — J Clin Endocrinol Metab 81 , — Hum Reprod 15 , — Fertil Steril 82 , — Lambalk CB Is there a role for follicle-stimulating-hormone receptor in familial dizygotic twinning? Lancet , — Hum Reprod 11 , — Baillieres Clin Obstet Gynaecol 7 , — Br Med J , — Oxford University Press is a department of the University of Oxford.
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