Differential Diagnosis for Infertility
The patient's presentation of infertility, regular menstrual cycles, and a history of previous pregnancy and miscarriage requires a comprehensive evaluation of potential causes. The following differential diagnosis is organized into categories:
- Single Most Likely Diagnosis
- Unexplained infertility: Given the patient's regular menstrual cycles, previous successful pregnancy, and lack of identifiable medical conditions, unexplained infertility is a strong consideration. The fact that she has been trying to conceive for 18 months without success, despite regular and frequent intercourse, also points towards this diagnosis.
- Other Likely Diagnoses
- Asherman's syndrome: The patient's history of dilation and curettage (D&C) after a miscarriage increases her risk for Asherman's syndrome, a condition characterized by intrauterine adhesions that can lead to infertility.
- Luteal phase defect: Although the patient's menstrual cycles are regular, a luteal phase defect could be contributing to her infertility. This condition is characterized by inadequate progesterone production, which can interfere with implantation of the embryo.
- Male factor infertility: The patient's husband's age (39 years) may be a contributing factor to their infertility, as male fertility declines with age.
- Do Not Miss Diagnoses
- Endometrial cancer: Although the patient's risk factors for endometrial cancer are not explicitly stated, it is essential to consider this diagnosis, especially given her history of unexplained infertility and heavy menstrual bleeding. Endometrial cancer can be asymptomatic, and a delay in diagnosis can have severe consequences.
- Ovarian cancer: Similar to endometrial cancer, ovarian cancer can be asymptomatic and may present with non-specific symptoms, including infertility. It is crucial to consider this diagnosis, especially in a patient with unexplained infertility.
- Rare Diagnoses
- Premature ovarian failure (POF): Although the patient's menstrual cycles are regular, POF can occur in women with regular cycles. However, this diagnosis is less likely given her age and previous successful pregnancy.
- Uterine anomalies: Congenital uterine anomalies, such as a septate uterus, can contribute to infertility. However, the patient's previous successful pregnancy makes this diagnosis less likely.
- Thyroid dysfunction: Although the patient has no thyromegaly, thyroid dysfunction can contribute to infertility. However, this diagnosis is less likely given her lack of symptoms and normal physical examination.