Hi, The BBT and temperature results are OK. The ultrasound is not showing any follicle on day 16 so you may have ovulated already. The best test to actually know if a woman is ovulating is ovulation study, where a scan is done every day. Starting from day 10 to see if a follicle is developing and if actual ovulation is taking place. Since this has not been done, prescribing Siphene directly will not give results. This is usually combined with an IUI [Intrauterine insemination procedure], that is direct instillation of semen into the uterus, as sometimes there are certain components in the cervical and vaginal secretions that do not allow ascent of sperms. Any abnormalities in sperm deposition in the vagina are also countered by this. Another important cause is problems in the sperm. If a semen analysis test has not been done, get your husband to do it as early as possible as 30% cases of infertility are due to problems in males. So, I suggest that you do an ovulation study and an IUI if ovulation is occurring after your husbands semen analysis. If there are no results with this, a laproscopy+hysteroscopy and an analysis of the endometrium for infection or abnormalities needs to be done. Hope this was helpful. Keep taking regular treatment and you will conceive. Thanks for using health care magic and best of luck.