Ok so you need to find out the day, but if you count exactly nine months back you should be able to narrow down the exact day. I would say sometime time in September/ early October. If you post the date, it would be easier for me to figure out. As you haven't provided an accurate date in June, it is estimated that she conceived around 9 September - 9 October.
31st March or thereabouts
Subtract fourteen weeks (7 days x 14) from the date of the ultrasound.
May
32 days previously
Around Jan1st
99% probability it was between 10 weeks & 10 weeks and 4 days ago.
just 11wks and 6 days before october18
around march 21 but no one can be 100% certain
16 weeks and 5 days before April 4, 2013 was Saturday, December 8, 2012.
Somewhere between 3rd and 9th December 2005.
July
Erm ... 20 weeks and four days ago ... Dohh!! Look at a calendar and count backwards 20 weeks, then backwards 4 days - there is your estimated date of conception.