Having only one fallopian tube does not necessarily prevent pregnancy. Many individuals with a single functioning fallopian tube can still conceive, often naturally.
Understanding Fallopian Tube Function
The fallopian tubes are muscular passageways connecting the ovaries and the uterus. Their primary role is to capture an egg released during ovulation and transport it towards the uterus.
Fertilization typically occurs in these tubes, as sperm travel from the uterus to meet the egg. Once fertilized, the embryo continues its journey through the fallopian tube to implant in the uterine lining. Tiny, hair-like structures called cilia, along with muscular contractions, help propel the egg or embryo.
Reasons for Having One Fallopian Tube
Individuals may have only one fallopian tube for several medical reasons. A common cause is surgical removal (salpingectomy), often necessary to treat an ectopic pregnancy. Ectopic pregnancies, where a fertilized egg implants outside the uterus, are not viable and can be life-threatening.
Other reasons for removal or damage include severe pelvic infections, endometriosis, or large ovarian cysts. A fallopian tube can also be congenitally absent, meaning an individual is born without one. A tube might also be present but non-functional due to blockages from scar tissue caused by infections like pelvic inflammatory disease (PID) or sexually transmitted infections (STIs).
The Possibility of Conception with One Tube
Conceiving with one fallopian tube is possible, as the remaining healthy tube can adequately perform the functions of two. This includes capturing an egg released from the ovary on the same side (ipsilateral ovulation).
The single fallopian tube can also pick up an egg released from the opposite ovary, a phenomenon called contralateral ovulation or transperitoneal migration. The fimbriae, finger-like projections at the tube’s end, are mobile and can sweep over either ovary to retrieve an egg. Studies indicate that a significant portion of pregnancies in individuals with one tube result from this cross-over mechanism, allowing the remaining tube to capture an egg even if released from the non-tubal side, facilitating fertilization and transport to the uterus.
Factors Influencing Fertility
While pregnancy with one fallopian tube is achievable, several factors can influence the chances of conception. The overall health and patency of the remaining tube are crucial; a healthy, unobstructed tube increases the likelihood of pregnancy.
Regular ovulation from at least one functioning ovary is essential. Age also plays a significant role, as egg quality and quantity naturally decline over time, particularly after age 35. General reproductive health, including the absence of other fertility issues like endometriosis, uterine fibroids, or issues with a partner’s sperm quality, also contributes to successful pregnancy.
Important Considerations for Conception
Individuals attempting to conceive with one fallopian tube should be aware of certain considerations. There is a slightly increased risk of ectopic pregnancy in the remaining tube, particularly if the initial loss was due to a prior ectopic pregnancy or tubal damage. Early medical confirmation of an intrauterine pregnancy is highly recommended.
If conception does not occur after a certain period, consulting a fertility specialist may be beneficial. For those under 35, this is typically after 12 months of regular, unprotected intercourse; for those over 35, after six months. A specialist can assess the remaining tube’s health, evaluate other fertility factors, and discuss options like fertility medications or assisted reproductive technologies such as in vitro fertilization (IVF), which bypasses the fallopian tubes.