Do couples with a history of spontaneous pregnancy followed by miscarriage have a higher chance of conception with Intrauterine Insemination (IUI) compared to other methods?

From the Guidelines

For couples with a history of spontaneous pregnancy followed by miscarriage, continuing to attempt natural conception for 6-12 months is the most recommended approach before considering fertility treatments like Intrauterine Insemination (IUI). This approach is based on the fact that these couples have already demonstrated the ability to conceive naturally, and the success rates for IUI in such cases are not substantially higher than natural conception rates in fertile couples 1.

Key Considerations

• The success rates for IUI in couples with unexplained infertility or those with prior natural conception are typically around 10-20% per cycle, which is comparable to natural conception rates in fertile couples.
• IUI might be considered if there are specific factors that could benefit from this intervention, such as mild male factor infertility, cervical mucus issues, or if the woman is over 35 and time is a concern.
• Recurrent miscarriage (defined as three or more consecutive pregnancy losses) warrants further investigation for underlying causes such as genetic, anatomical, hormonal, or immunological factors before determining the most appropriate treatment path.

Evidence-Based Recommendations

• Expectant management for at least 6 months is recommended for couples with unexplained infertility and a good prognosis of becoming pregnant without assistance 1.
• IUI with ovarian stimulation (OS) is recommended in couples with unexplained infertility and men with a total motile sperm count (TMSC) > 10 million as the first treatment option, especially when the prognosis of natural conception is poor 1.
• The use of IUI should be withheld when more than two dominant follicles >15 mm or more than five follicles >10 mm at the time of HCG injection or LH surge are present to maintain singleton delivery rates 1.

Conclusion Not Provided as per Guidelines

Instead, the key points to consider for couples with a history of spontaneous pregnancy followed by miscarriage are:

• Natural conception attempts for 6-12 months before considering fertility treatments.
• Specific factors that may benefit from IUI intervention.
• Investigation into underlying causes for recurrent miscarriages.
• Evidence-based recommendations for expectant management and IUI with OS.

From the Research

Intrauterine Insemination (IUI) and Conception

• Couples with a history of spontaneous pregnancy followed by miscarriage may have a higher chance of conception with IUI compared to other methods, but the evidence is not directly relevant to this specific question.
• A study on subfertile couples who experienced a miscarriage after a previous period of subfertility found that they have very good prospects of a spontaneous ongoing pregnancy in the near future 2.
• Another study compared double IUI to single IUI in stimulated cycles for subfertile couples and found that the evidence was of low quality, but suggested that double IUI may increase clinical pregnancy rate compared to single IUI 3.

Factors Affecting IUI Outcomes

• A review of predictive factors for IUI outcomes found that infertility diagnosis, semen parameters, and stimulation regimens can affect IUI outcomes, including clinical pregnancy rate, live birth rate, spontaneous abortion rate, and multiple pregnancy rate 4.
• The review also found that IUI is most effective for women with ovulatory dysfunction and unexplained infertility, and least effective for women with tubal factor and stage III-IV endometriosis 4.

Spontaneous Pregnancy and Recurrent Pregnancy Loss

• A study on fertile patients with recurrent pregnancy loss found that 88% of patients who attempted spontaneous conception conceived within 6 months, with a median time of 2 months 5.
• The study also found that the live birth rate and clinical miscarriage rate was not improved with any fertility treatment, including IUI, IVF, and PGS 5.
• Another study found that subfertile couples who have unsuccessfully or successfully experienced fertility treatments have a higher probability of spontaneous pregnancy if they are younger and have a smaller number of IVF attempts 6.