Natural conception following endometriosis surgery

This study looked at how the Endometriosis Fertility Index (EFI) affected patients following endometriosis surgery. It found that patients with a better EFI score conceived naturally more often, while more patients with a low score became pregnant using assisted reproduction.

Endometriosis is a chronic condition in which cells from the lining of the uterus grow in other locations. This can include the Fallopian tubes, the ovaries, or within the abdomen. Endometriosis can cause pain, heavy bleeding, and infertility.

Surgery to remove endometriosis lesions can improve many of the symptoms. However, the extent of the endometriosis can affect how successful surgery will be. The Endometriosis Fertility Index (EFI) was developed to predict natural conception following surgery. The EFI includes many factors such as the amount of time trying to conceive, how widespread the lesions are, and how much tissue the surgeon was able to preserve. The EFI scale ranges from 0 to 10. Women with higher scores are more likely to become pregnant following surgery.

It is not clear how women and their doctors should use EFI scores to decide between trying naturally or using assisted reproductive technologies (ART).

This study used records from 234 patients with endometriosis who underwent surgery to improve fertility. None of the patients had a condition requiring the immediate use of ART, such as for major male factor infertility. There were patient records for 29.7 months after surgery on average. The patient records were divided into two groups. The high EFI group had scores of 5 – 10, while the low EFI ranged from 0 – 4.

44.4% of patients became pregnant following surgery. Of the patients who became pregnant, 55.8% became pregnant through natural conception.

Patients with a low EFI score became pregnant naturally 53% less often. However, those with low EFI scores also became pregnant using ART 90% more often. Women with a low EFI score were most likely to conceive naturally 6 – 12 months after surgery, with a 2.4% monthly chance. No patients with a low EFI score became pregnant more than 18 months after surgery.

Women with a high EFI score had natural conceptions for a longer window of time, until 36 months after surgery. They had the most natural conceptions 18 – 24 months after surgery, with a 2.1% chance.

This study found that women with a high EFI score more often conceived naturally following endometriosis surgery. The authors suggest that these women should be referred to ART shortly after surgery.

EFI is already used to counsel patients whether to pursue natural or assisted conception following surgery. This study did not include information on how many patients used ART, or how long they tried naturally.