Narrated Jabir:

Jews used to say: "If one has sexual intercourse with his wife from the back, then she will deliver a squint-eyed child." So this Verse was revealed:-- "Your wives are a tilth unto you; so go to your tilth when or how you will." (2:223)

حَدَّثَنَا أَبُو نُعَيْمٍ، حَدَّثَنَا سُفْيَانُ، عَنِ ابْنِ الْمُنْكَدِرِ، سَمِعْتُ جَابِرًا ـ رضى الله عنه ـ قَالَ كَانَتِ الْيَهُودُ تَقُولُ إِذَا جَامَعَهَا مِنْ وَرَائِهَا جَاءَ الْوَلَدُ أَحْوَلَ‏.‏ فَنَزَلَتْ ‏{‏نِسَاؤُكُمْ حَرْثٌ لَكُمْ فَأْتُوا حَرْثَكُمْ أَنَّى شِئْتُمْ‏}‏