Calculating ovulation after a miscarriage can be difficult, because the menstrual cycle may be disrupted or irregular. However, there are several methods that can help you estimate when your body is most likely to ovulate without having a period. One of the simplest and most reliable ways to calculate ovulation is by tracking your basal body temperature (BBT) each morning with a thermometer. BBT increases slightly during ovulation, so if you take it every day for at least two weeks, you'll see a pattern emerge as to when your fertile window begins and ends. Additionally, measuring changes in cervical mucus throughout the month can also provide clues about impending ovulation - as estrogen levels rise just before an egg is released from the follicle; cervical mucus becomes more profuse and less viscous. Finally, another method for calculating potential fertility windows is through urine testing strips which measure hormone levels related to fertility such as luteinizing hormone (LH). LH surges 24-36 hours prior to ovulation so these tests can give you insight into when you’re most likely to conceive naturally or use assisted reproductive technologies successfully.